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151.
BACKGROUND: An estimated 35 million Americans experience significant apprehension about dental procedures, while an additional 10 to 12 million are considered to be "dental phobic" and avoid needed dental care altogether. Nitrous oxide is a general anesthetic used at subanesthetic concentrations to reduce anxiety during dental procedures. The purpose of this study was to characterize mood changes during nitrous oxide inhalation in patients with different levels of preoperative dental anxiety. METHODS: Forty-six patients who were to receive nitrous oxide during a dental procedure completed two anxiety scales. These patients were categorized into three groups: low anxiety, or LA, moderate anxiety, or MA, and high anxiety, or HA. They completed a visual analog scale of subjective effects before, during and after the dental procedure. RESULTS: A number of visual analog ratings, the majority of which could be considered pleasant, increased during nitrous oxide administration. It is significant that this increase in pleasant mood occurred in the HA and MA groups to the same degree as it did in the LA group. Patients in the HA and MA groups had elevated preoperative visual analog ratings of "anxious" that were reduced during nitrous oxide administration to a level equivalent to that reported by patients who had low preoperative anxiety. Patients in the HA group also had elevated preoperative visual analog ratings of "having unpleasant thoughts" and "feel bad" compared with the LA group. These ratings were reduced in the HA group to a level equivalent to that reported by patients in the LA group. CONCLUSIONS AND CLINICAL IMPLICATIONS: Regardless of their preoperative anxiety level, patients experienced a number of mood-altering effects during nitrous oxide inhalation, the majority of which could be considered pleasant. Ratings of an unpleasant nature decreased markedly in patients with high anxiety. These findings suggest that nitrous oxide may be an effective therapy in reducing patient anxiety during dental procedures.  相似文献   
152.
BACKGROUND: This article is the first of two that focus on recent changes in the funding of dental services in the United States. METHODS: This study is based on analyses of data regarding dental expenditures among children 2 to 17 years of age from the 1987 National Medical Expenditure Survey and the 1996 Medical Expenditure Panel Survey. Both of these surveys were designed to produce national estimates of annual medical expenditures in the United States. RESULTS: Overall, real per capita dental expenditures among 2- to 17-year-old children who had had a dental visit fell from $578.05 in 1987 to $498.57 in 1996. Large increases per patient were reported for the poorest children, while decreases were reported for children from families with higher incomes. CONCLUSIONS: Much of the increase from 1987 to 1996 in dental expenditures among economically disadvantaged children who had had a dental visit was due to an increase in care provided by dentists that was not reimbursed. PRACTICE IMPLICATIONS: More needs to be done to increase the number of economically disadvantaged children who visit a dentist. All segments of society must cooperate to achieve this result.  相似文献   
153.
Chest pain does not necessarily indicate cardiac disease. The most common causes of acute chest pain encountered in dental situations include hyperventilation, pulmonary embolism, angina pectoris and myocardial infarction. Stress and fear often cause rapid breathing or hyperventilation. This usually occurs in young adults and although the hyperventilating patient often complains of chest pain, this is rarely a manifestation of cardiac disease. Pulmonary embolism usually indicates the occlusion of a pulmonary artery causing severe chest pain. The primary clinical manifestation of angina pectoris is chest pain. Although most instances of anginal pain are easily terminated, the dentist must always consider the possibility that the supposed anginal attack is actually a sign of acute myocardial infarction (AMI). AMI is a clinical syndrome caused by a deficient coronary arterial blood supply to a region of myocardium that results in cellular death. There is a high incidence of mortality among AMI with death often occurring within 2 hours of the onset of signs and symptoms. The initial clinical manifestations of all types of chest pain can be similar. Therefore the dentist must develop proficiency in constituting a differential diagnosis and an efficient management protocol. As in most medical situations prevention is the most powerful tool. However, if chest pains do occur, measures such as airway management, oxygen supplementation, coronary artery dilation, analgesis and in extreme cases, cardiopulmonary resuscitation and evacuation to the emergency room, may be necessary.  相似文献   
154.
INTRODUCTION: The objective structured clinical examination (OSCE) is now an accepted tool in the assessment of clinical skills in dentistry. There are however no strict or limiting guidelines on the types of scenario that are used in the OSCE examinations and experience and experimentation will inevitably result in the refinement of the OSCE as a tool for assessment. AIM: The aim of this study was to compare and contrast different types of clinical operative skills scenarios in multi-station OSCE examinations. METHODOLOGY: Student feedback was obtained immediately after the sitting of an OSCE examination on two different occasions (and two different cohorts of students). The same questionnaire was used to elicit the responses. RESULTS: The questionnaire feedback was analysed qualitatively with particular regard to student perception of the usefulness and validity of the two different kinds of OSCE scenarios. CONCLUSIONS: OSCE scenarios which involve phantom heads are perceived to lack clinical authenticity, and are inappropriate for the assessment of certain clinical operative skills. While the OSCE is useful in the examination of diagnostic, interpretation and treatment planning skills, it has apparent limitations in the examination of invasive operative procedures.  相似文献   
155.
External distraction of the maxilla in patients with craniofacial dysplasia   总被引:3,自引:0,他引:3  
Patients with severe maxillary hypoplasia secondary to craniofacial dysplasia present a challenge to the craniofacial surgeon. Maxillary distraction presents a promising tool to treat these patients more successfully. Fifteen patients aged 12 to 20 years with craniofacial dysplasia and maxillary retrusion were treated with two different techniques after complete Le Fort I osteotomy: one group underwent face mask protraction (2 patients), and the other group underwent rigid external distraction (13 patients). Cephalometric evaluation was performed before and after distraction. Rigid external distraction appeared to be superior to face mask protraction. Maxillary retrusion was fully corrected in this group. The path of maxillary positioning was well controlled by changing the traction force vector. Distraction osteogenesis has certainly improved treatment of these patients.  相似文献   
156.
With the latest developments of the Procera® system, all-ceramic crowns have become an attractive solution to provide functional and esthetic rehabilitation on teeth and dental implants. The Procera AllCeram crown and Procera Abutment embrace the concept of computer-assisted design and computer-assisted machining (CAD/CAM) and can be used together for optimal esthetic result. The purpose of this case report was to illustrate the advantages of these new components for complex anterior rehabilitation. Three natural teeth and a Procera Abutment were restored using four Procera AllCeram crowns. Treatment planning and esthetic benefits are discussed.
CLINICAL SIGNIFICANCE
For complex anterior rehabilitations, the Procera system fulfills both functional and esthetic objectives, providing a new way in the field of esthetic and restorative dentistry. Nevertheless, planning and preparation stages are decisive for successful treatment.  相似文献   
157.
The presence of foreign biological substances in the human body can lead to violent immune reactions. This is the report of a very rare case involving not only the presence of a biological substance, but also a symbiotic relationship between a living plant (the common wheat grain, Triticum aestivum L.) and the human body. Black coal particles and one cereal grain were removed from the subgalea of the right parietal region of a 35-year-old man who had sustained injuries in a motor vehicle accident 16 days earlier. There were signs of germination of the grain, but no macroscopic or microscopic evidence of an inflammatory reaction. Grain germination was verified microscopically. There are various explanations for the absence of an immune reaction, but only coal-tar-induced immunosuppression can explain the observed phenomenon.  相似文献   
158.
The interaction between epithelial and mesenchymal tissues plays a critical role in the development of organs such as teeth, lungs, and hair. During tooth development, fibroblast growth factor (FGF) signaling is critical for regulating reciprocal epithelial and mesenchymal interactions. FGF signaling requires FGF ligands and their receptors (FGFRs). In this study, we investigated the role of epithelial FGF signaling in tooth development, using the Cre-loxp system to create tissue-specific inactivation of Fgfr1 in mice. In K14-Cre;Fgfr1(fl/fl) mice, the apical sides of enamel-secreting ameloblasts failed to adhere properly to each other, although ameloblast differentiation was unaffected at early stages. Prior to eruption, enamel structure was compromised in the K14-Cre;Fgfr1(fl/fl) mice and displayed severe enamel defects that mimic amelogenesis imperfecta (AI), with a rough, irregular enamel surface. These results suggest that there is a cell-autonomous requirement for FGF signaling in the dental epithelium during enamel formation. Loss of Fgfr1 affects ameloblast organization at the enamel-secretory stage and, hence, the formation of enamel.  相似文献   
159.
Biocompatibility of various root canal filling materials ex vivo   总被引:1,自引:0,他引:1  
Aim  To evaluate the biocompatibility of a resin-based endodontic filler (RealSeal) using the indirect cytotoxicity test.
Methodology  Human gingival fibroblasts were cultured ex vivo . Pellets of the materials to be tested were incubated for 24, 48, and 72 h at 37 °C under sterile conditions to obtain their eluates. The fibroblasts were exposed to either diluted (50%) or undiluted eluates for 24 h. A culture medium with foetal calf serum was added to the control wells. Cell viability was estimated by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide method. The data concerning cell viability were statistically analyzed using one-way anova test and Bonferroni multiple comparisons test.
Results  Eluates obtained after 24 h of incubation with the resin filler did not reduce cellular viability. An increase in cellular viability, as compared with control cells, was observed in the gutta-percha group. The undiluted eluate from the polyether material was cytotoxic, causing an 82 ± 4% decrease in cellular viability. Eluates obtained after 48 h of incubation with the resin filler increased cellular viability, whereas the polyether significantly reduced viability. Gutta-percha did not cause any detectable change. After 72 h of incubation the eluate of the resin filler caused an increase in cellular viability, as did gutta-percha, whereas polyether caused a significant decrease.
Conclusions  RealSeal resin filler was nontoxic in this laboratory model. Further investigations are necessary to verify its usefulness in clinical applications.  相似文献   
160.
Abstract – Objectives: The Early Childhood Oral Health Impact Scale (ECOHIS) is a recently developed oral health‐related quality of life instrument designed to assess the impact of oral health problems in 0–5‐year‐old children. It has previously been validated as discriminative instrument. The goal of this study was to investigate the responsiveness to change of the ECOHIS. Methods: Data were collected from a convenience sample of 101 parents of 0–5‐year‐old children attending a hospital dental clinic for dental treatment. The ECOHIS was completed by parents prior to dental treatment and 2 weeks later. Subjects were also asked a global transition judgement concerning change between the second and first completion of the ECOHIS instrument. Responsiveness to change of the ECOHIS was analysed through: (i) a comparison of ECOHIS change scores with a global transition judgment by study subjects; (ii) an assessment of the statistical significance of within‐group change in scores over time for groups reporting improvement, stability and deterioration; (iii) an estimation of the ECOHIS’s sensitivity; and (iv) an investigation the effect size of the ECOHIS. Results: Of the 101 subjects recruited, 94 had full datasets. Their data were used for the analyses reported in this paper. Pre‐ and post‐treatment distributions of ECOHIS scores were strongly distributed towards no oral health impacts. Among the 94 subjects, 51.1% reported improvement, 42.6% reported no change and 6.4% reported deterioration following treatment, using the global transition judgement. The mean ECOHIS change scores for these three groups were ?0/9, +0.7 and +6.5 respectively, although none of the within‐group changes were statistically significant. The effect size for those reporting improvement was small (0.15) but for those reporting deterioration was moderate‐to‐large (0.69). Sensitivity ranged from 0.61–0.79 depending on the size of the cut‐off point, with a change of 3 points demonstrating the best sensitivity to false positive ratio (0.79 versus 0.41 respectively). Conclusion: In this sample with low levels of problems, the ECOHIS has demonstrated some limited ability to respond to change. Further work in a larger sample with higher levels of problems is needed to investigate the instrument’s ability to respond to change when it has occurred.  相似文献   
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